Cylinder lock

ABSTRACT

A pick-proof cylinder lock whose cylinder may rotate in either direction, for example, to unscrew the lock from a threaded recess in a vending machine. The lock includes a locking disc mounted at one end of the detent stack. The disc is provided with a plurality of teeth which engage a corresponding plurality of gaps in the lock cylinder.

United States Patent 1151 3,699,790 Ansala 1 Oct. 24, 1972 54] CYLINDER LOCK 2,565,659 8/1951 Kontra ..7 0/140 x 72] Inventor; v i Toivo Ansala, Jatasalmenfie, 2,584,708 2/ 1952 Jenkins ..70/ 140 X Helsinki 3 Finland 2,832,211 4/1958 Saarento ..70/364 R [22] Filed: April 1971 Primary Examiner-Albert G, Craig, Jr. 21] Appl. No.: 131,256 Att0mey--Kurt Kelman [30 Foreign Application Priority Data [57] ABSTRACT Sept. 8, 1970 Finland .2472 A Pick-Pmof cylinder whse cylinder my mate in either direction, for example, to unscrew the lock 52] us. c1 ..70/364 R, 70/86, 70/140 fmm a threaded recess in a vending machine- The 51 Int. Cl. ..E05b 21/06 lock includes a locking disc mounted at one end of the [58] Field oi Search ..70/77, 78, 85, 86, 140,216, detem stack- The disc is Provided with a plurality of 7 0/230, 364 R teeth which engage a corresponding plurality of gaps in the lock cylinder.

56 R f Cited 1 e 4 Claims, 5 Drawing Figum UNITED STATES PATENTS 1,218,065 3/1917 Diesel ..V..7...70/364 R CYLINDER LOCK Cylinder locks may be divided into two groups. The first group includes the locks of the so-called Yale type, in which the locking detents move into the opening position when the key is inserted. Subsequently, the cylinder may be turned either in clockwise or in counterclockwise direction. A shortcoming of this type of lock is, however, that the lock is easy to pick. To the other group belong cylinder locks in which the detents can be displaced into opening position only when the key is turned. The advantage of such locks, compared to those mentioned above, is that they are more difficult to pick. It is a drawback, however, that in this latter type of lock the cylinder can only be turned in one direction, that is in the direction in which the key was turned in order to bring the detents into opening position.

Quite a number of attempts have been made to combine the advantages of both above-mentioned lock types and to avoid their drawbacks. The object of the invention is to provide a lock in which the turning of the key moves the detents into opening position, whereupon the cylinder may be turned in the operating direction and also in opposite direction. The present invention has particular reference to a cylinder lock of this kind, and the above-mentioned object has been achieved by provision of a cylinder lock in which, at the end of the stack of detents, a disk is positioned which, by tooth engagement, takes the cylinder along with it when the key is turned opposite to the operating direction.

The invention is described in greater detail in the following detailed description, with reference to the attached drawings, wherein FIG. 1 shows a longitudinal section of the cylinder lock,

FIG. 2 is a cross sectional view at a detent, taken along the line IIII in FIG. 1,

FIG. 3 is a sectional view at the locking disk, along line III-III in FIG. 1,

FIG. 4 shows the locking disk, seen in the direction of the keyhole, and

FIG. 5 shows the locking disk in elevational view.

A typical use for the lock according to the invention is for coin boxes such as are used in various vending machines, in coin-operated washing machines, etc., where the cylinder of the lock is coupled with a threaded bolt, which, in turn, by rotation is locked in a nut which is welded to the body, inside the machine. In these embodiments the necessity arises to turn the lock cylinder in both the clockwise and counterclockwise direction. However, a lock according to the invention may also be used for other purposes and it is always advantageous when in addition to a given operation another operation is required which is achieved by turning the cylinder in the direction opposite to the operating direction.

In FIG. 1 the lock has been depicted in locked position, in which the detents 7 prevent the lock cylinder 2 from turning with reference to the case 3 of the lock. The number of detents 7 is ten in the case illustrated and, as shown the catches of the detents have entered the grooves 1 in the lock case 3. The detents are otherwise identical, but they have five different positions for the key. The number of key combinations is therefore 5" 9,765,625. When the detents are in the abovementioned closing position, the keyholes in the detents are aligned in the direction of the lock axis.

For opening the lock, the key is inserted in the keyhole 14, and the key is then turned 35 degrees in the operating direction, or clockwise in FIGS. 2 and 3. The cuts in the key will then pull the detents out of the locking grooves 1 so that the ends of the catches of the detents become located on the circumference between the lock case 3 and the detent cylinder 2, whereby the detent cylinder 2' is free to turn clockwise when the key is turned further. In this manner normal movement of the pin 13 at the end of the-detent cylinder is accomplished.

If in the lock just described, which does not have the special features according to the invention to be described below, the key is turned in the reverse or counterclockwise direction, the detents will immediately enter the grooves 1 and the lock becomes locked. No second mode of operation may therefore be achieved by turning the key in the opposite direction. To eliminate this drawback, in the lock described above, a locking disc 4 is placed at one end of the stack of detents. This locking disk is separately seen in FIGS. 4 and 5. The locking disk is flat in shape and has a circular contour. The disk has an opening 9 there-in corresponding in its shape to the end of the key and on both sides of this opening, a pair of stop lugs 8. When the end of the key is in the opening 9, turning motion of the key also causes the locking disk 4 to turn. While the key is being pushed into the lock, the locking lugs 8 are in a position in which they enter the-tooth gaps 5 on the bottom of the detent cylinder 2. When the key is turned in order to bring the detents into opening position, the locking disk 4 turns along with the key and the locking lugs 8 slide along the inclined surfaces of the tooth gaps 5, whereby the locking disk and the entire detent stack move towards the left in FIG. 1 a distance equivalent to the pitch of the surfaces-5 over 35 degrees of the tuming motion of the key. The spring 10' in the lock case then urges the locking disk 4 once more to the right in so that the locking lugs 8 enter the tooth gaps 6, whereby the entire detent stack moves to the right.

In this above-described position the key may be turned counterclockwise, or in the reverse operating direction, even several turns, whereby the threaded bolt 13 connected to the end'of the detent cylinder is screwed out of the nut to enable the coin box to be opened. After the box has been emptied, the key is once more turned clockwise, whereby the threaded bolt is locked in its nut. When the key is drawn in the direction away from the lock, the conical spring 10 is compressed and the locking disk 4' follows in the same direction along with the detent stack, both being urged by the spring 12.

The invention is not confined to the embodiment presented in the foregoing description and illustrated by the drawings; several deviating modifications are possible within the scope of the patent claims presented below. For instance, the fundamental idea of the invention is also realizable in locks of other types than have been stated in the foregoing. The invention as such is practical in locks in which turning motion of the key turns the detents into their opening positions, in which the circumferential notches of the detent plates are on one straight line, constituting a groove into which a bar may enter, which otherwise locks the detent cylinder to be immovable with reference to the lock case.

i claim:

1. A cylinder lock which comprises 1. a lock housing;

2. a lock cylinder rotatably positioned in said hous- 3. a stack of detents within said lock cylinder, each engaging a groove in said lock housing, to inhibit rotation of said cylinder, insertion of an appropriately recessed key and rotation thereof in a first direction moving said detents out of engagement with said groove and thereby permitting rotation of said cylinder in said first direction; and

4. means coupled to one end of said stack of detents for engaging said cylinder and rotating the same, together with said detent stack, when said key is rotated in a second direction.

2. The cylinder lock according to claim 1, wherein said engaging means comprises a locking disc having an aperture therein to receive the end of said key; a plurality of teeth on said disc; and a corresponding plurality of tooth gaps on the bottom surface of said cylinder, each tooth gap having an inclined surface whereby said stack of detents is moved along the axis of said key when said cylinder is rotated in said first direction.

3. The cylinder lock according to claim 2, further comprising spring means, positioned intermediate the key-hole end of said lock housing and said cylinder, for biassing said detent stack and disc into engagement with said bottom surface of the cylinder.

4. The cylinder lock according to claim 3, further comprising second spring means, positioned intermediate said disc and the bottom surface of said cylinder, for maintaining said disc in engagement with said detent stack when said stack is moved along the axis of said key. 

1. A cylinder lock which comprises
 1. a lock housing;
 2. a lock cylinder rotatably positioned in said housing;
 3. a stack of detents within said lock cylinder, each engaging a groove in said lock housing, to inhibit rotation of said cylinder, insertion of an appropriately recessed key and rotation thereof in a first direction moving said detents out of engagement with said groove and thereby permitting rotation of said cylinder in said first direction; and
 4. means coupled to one end of said stack of detents for engaging said cylinder and rotating the same, together with said detent stack, when said key is rotated in a second direction.
 2. a lock cylinder rotatably positioned in said housing;
 2. The cylinder lock according to claim 1, wherein said engaging means comprises a locking disc having an aperture therein to receive the end of said key; a plurality of teeth on said disc; and a corresponding plurality of tooth gaps on the bottom surface of said cylinder, each tooth gap having an inclined surface whereby said stack of detents is moved along the axis of said key when said cylinder is rotated in said first direction.
 3. The cylinder lock according to claim 2, further comprising spring means, positioned intermediate the key-hole end of said lock housing and said cylinder, for biassing said detent stack and disc into engagement with said bottom surface of the cylinder.
 3. a stack of detents within said lock cylinder, each engaging a groove in said lock housing, to inhibit rotation of said cylinder, insertion of an appropriately recessed key and rotation thereof in a first direction moving said detents out of engagement with said groove and thereby permitting rotation of said cylinder in said first direction; and
 4. means coupled to one end of said stack of detents for engaging said cylinder and rotating the same, together with said detent stack, when said key is rotated in a second direction.
 4. The cylinder lock according to claim 3, further comprising second spring means, positioned intermediate said disc and the bottom surface of said cylinder, for maintaining said disc in engagement with said detent stack when said stack is moved along the axis of said key. 